Dataset Information

Retron Eco2 breaks tRNAs for anti-phage defense

ABSTRACT: Retrons mediate bacterial anti-phage defense by reverse transcribing non-coding RNA into multicopy single-stranded DNA (msDNA). Our study reveals the unique trimeric nucleoprotein structure of Eco2, which solely relies on a single protein for defense, unlike most other retrons. This structure supports an msDNA-dependent regulation of the Eco2's reverse-transcriptase and TOPRIM/RNase H (TR) fusion protein. We also show that Eco2's broad defense against various phages is triggered by a phage-encoded endonuclease that degrades the msDNA. msDNA decay in turn activates the TR domain for tRNA cleavage, resulting in shutdown of gene expression for abortive infection. Our findings not only advance the understanding of Eco2’s biogenesis and defense mechanism but also provide a structural basis for engineering of this system.

INSTRUMENT(S):

ORGANISM(S): Escherichia Coli

SUBMITTER: Wieland Steinchen

LAB HEAD: Gert Bange

PROVIDER: PXD060313 | Pride | 2026-02-03

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	240829_HX_067_Mi_Apo.zip	Other
	240829_HX_067_Mi_Eco2.DnX	Other
	240829_HX_067_Mi_PLGS.zip	Other
	240829_HX_067_Mi_msDNA.zip	Other
	DescriptionOfRawDataFiles.xlsx	Xlsx

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Publications

Structure and mechanism of antiphage retron Eco2.

Jasnauskaitė M M Juozapaitis J J Liegutė T T Grigaitis R R Skorupskaitė A A Steinchen W W Mikšys A A Truncaitė L L Kazlauskaitė K K Torres Jiménez M F MF Khochare S S Dudas G G Bange G G Malinauskaitė L L Songailienė I I Pausch P P

Nature structural & molecular biology 20260218 2

Retrons are prokaryotic reverse transcriptase systems that produce multicopy single-stranded DNA (msDNA), yet the principles by which they mediate antiviral defense remain largely unresolved. Here we investigate the mechanism of Escherichia coli Eco2, a minimal retron composed of a single reverse transcriptase-nuclease fusion protein. Cryogenic electron microscopy and hydrogen/deuterium exchange mass spectrometry reveal the structures and dynamics of a trimeric nucleoprotein complex assembled wi ...[more]

PMID: 41709047

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